Cisco 400-007 Exam With Confidence Using Practice Dumps

When a service provider does not support multicast over their Layer 3 VPN, the enterprise can useGRE tunnels between Customer Edge (CE) devicesto transport multicast traffic. This method allows the customer to encapsulate multicast packets in unicast GRE packets, which are routable through the provider’s non-multicast core.

In this scenario, the most scalable and immediate solution is to establish a GRE tunnel betweenC2 (in the head office CE router path)andC4 (at the branch office). This setup ensures that multicast traffic originating at the head office is tunneled directly to the multicast receivers, bypassing the service provider’s non-multicast-aware core.

This strategy is directly aligned with CCDE v3.1 principles, which emphasize:

Minimizing service provider dependency

Providing a scalable, customer-controlled overlay solution

Ensuring protocol compatibility across domains

Why other options are incorrect:

A: Tunnel between CE1 and CE2 is less optimal, as it may not originate or terminate at the exact multicast endpoints.

C: Tunnel between C1 and C4 is less aligned with CE-to-CE design expectations and may bypass required edge security/policy controls.

D: 2547oDMVPN is more complex and intended for full-scale VPN overlays, not quick multicast solutions.

E: Draft Rosen requires service provider support, which is currently unavailable, hence not a valid short-term option.

This solution ensures operational simplicity and future scalability with minimal provider dependency, which are core principles outlined in the CCDE v3.1 design methodology.

C (Service orchestration platform):As branch scale increases, orchestration platforms automate multi-site deployment, configuration, and policy management. They integrate with controllers and external systems to reduce manual intervention, improve scalability, and enforce service consistency across thousands of locations.

Other options explained:

A: Management systems assist monitoring but don’t address provisioning complexity.

B: Lifecycle models guide processes but are not technical automation solutions.

D: Manual teams are not scalable for high-volume growth.

When an ACL is applied inbound on the Internet gateway interface facing the internal (trusted) network, the source IP address seen in the ACL will be the address after NAT translation has been applied to outbound traffic. This is called the inside global address:

Inside global = Public IP assigned by NAT to inside traffic for external use.

Inside local = Internal IP address prior to NAT.

Why other options are incorrect:

B, D: Outside addresses refer to external devices, not internal traffic.

C: Inside local is seen before NAT, not after.

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